The present invention relates to eps15 homology (EH) domain containing proteins, to polynucleotide sequences encoding said EH domain containing proteins, to oligonucleotides and oligonucleotide analogs derived from said polynucleotide sequences, to a display library displaying short peptides derived from said EH domain containing proteins, to antibodies recognizing said EH domain containing proteins, to peptides or peptide analogs derived from said EH domain containing proteins, and to pharmaceutical compositions and methods of employing said peptides or peptide analogs, said oligonucleotides and oligonucleotide analogs, and/or said polynucleotide sequences to up-regulate or down-regulate clathrin coated pit mediated endocytosis and thereby insulin growth factor 1 receptor (IGF1 receptor) signaling.
Citation or identification of any reference in this section or in any other section of this application shall not be construed as an admission that such reference is available as prior art to the present invention.
Abbreviations used herein include APxe2x80x94adaptor protein complex; BBSxe2x80x94Bardet-Biedl Syndrome; ECLxe2x80x94enhanced chemiluminescence; EGFRxe2x80x94epidermal growth factor receptor; EHxe2x80x94eps15 homology; Epsxe2x80x94epidermal growth factor receptor-pathway-substrate; ESTxe2x80x94expressed sequence tag; GFPxe2x80x94green fluorescent protein; HRPxe2x80x94horseradish peroxidase; IGF1xe2x80x94insulin-like growth factor 1; ocdxe2x80x94osteochondrodystrophy; ORFxe2x80x94open reading frame; PBSxe2x80x94phosphate buffered saline.
The diverse effects growth factors have on cell proliferation, differentiation and metabolism are mediated by interaction with cell surface receptors. There are several receptor families which convey their ligand-induced signals through different intracellular mechanisms. One family of receptors posses tyrosine kinase activity (Darnell et al., 1995) and includes the EGF receptor, insulin receptor and the IGF1 receptor. Binding of these receptors to their ligands induces cascade of events, leading to sequestration of the ligand bound receptor in endocytic vesicles (Kirchhausen et al., 1997; Mukherjee et al., 1997; Warren et al., 1998). This process depends on the specific interaction of clathrin and the clathrin adaptor protein complex, AP-2, with specific accessory factors. It has been shown that the EGFR phosphorylates at least two proteins, eps15 and eps15R, after which each one of them may interact, through accessory proteins, with AP-2.(Benmerah et al., 1998; Coda et al., 1998). This interaction leads to endocytosis of the ligand bound EGFR. Pan1p, the yeast homologue of eps15, was also shown to function as a multivalent adaptor that coordinates proteinxe2x80x94protein interactions essential for endocytosis (Wendland and Emr, 1998).
Ligand induced endocytosis is a regulated process, leading to the formation of clathrin coated pits containing the ligand bound receptor. The spontaneous polymerization of clathrin triskelions is thought to cause the pits to expand and eventually to form the clathrin coated vesicle. These vesicles loose their coat after endocytosis, forming the early endosome. Endocytosed receptors, after their dissociation from the ligand due to the low pH in the early endosome, are usually recycled to the plasma membrane or are destined to the lysosomes, were they are degraded. For EGF receptor, the phosphorylation of eps15 leads, most probably, to binding of at least another specific protein, epsin,(Chen et al., 1998) and this protein complex seems to recruit AP-2. (Iannolo et al., 1997)., which then binds to clathrin.
Eps15 and eps15R contain three domains: One is an N-terminal domain containing three repeats of the EH motif, directing proteinxe2x80x94protein interactions through the amino acids NPF (asparagine-proline-phenylalanine, SEQ ID NO: 11) of target proteins. The EH domain spans about 100 amino acids, about 50% of which are conserved between different proteins containing this domain. EH domains are frequently present in multiple copies and might also include EF-hand calcium binding motifs. It has been shown that the second EH domain consists of a pair of EF hand motifs, the second of which binds tightly to Ca2+. The NPF containing motif binds in a hydrophobic pocket of the EH domain, between two alpha helices, and the binding is mediated by a critical aromatic interaction (Benmerah et al., 1998; de Beer et al., 1998; Di Fiore et al., 1997; Fazioli et al., 1993; Schumacher et al., 1995; Tebar et al., 1997). A second domain contains heptad repeats, characteristic of coiled-coil structure, which directs dimerization (and most probably oligomerization). The third domain is C-terminal region and has a proline-rich region and a repeated DPF (aspartic acid-proline-phenylalanine, SEQ ID NO:12) motif.(Benmerah et al., 1998; Di Fiore et al., 1997; Fazioli et al., 1993; Schumacher et al., 1995; Tebar et al., 1997).
There is a growing number of EH-containing proteins, like intersectin .(Yamabhai et al., 1998) Ese1 and Ese2 (Sengar et al., 1999) and they all seem to be associated with the intracellular routing machinery (Di Fiore et al., 1997). Another EH containing protein is the Drosophila Dap160, a neural specific protein that anchors proteins required for endocytosis. (Roos and Kelly, 1998). It has been suggested that endocytosis is only one of several intracellular activities in which EH containing proteins participate and may also regulate (Coda et al., 1998).
Several proteins, containing NPF motifs, have been identified as interacting with eps15 and participating in clathrin coated pit mediated endocytosis, like: epsin (Chen et al., 1998) and dynamin,(Roos and Kelly, 1998).
While reducing the present invention to practice, two new and highly homologous genes isolated from both human and mouse, named EHD 1 (which is referred to in U.S. Pat. No. 09/026,898 as testiline and has the yet unpublished accession Nos. AF099011 for the human cDNA and AF099186 for the mouse cDNA) and EHD2 were cloned, sequenced, mapped, their expression characterized and function analyzed. The proteins encoded by the isolated genes contain an EH domain which, as described above, is known to modulate interactions with endocytic vesicles. Based on the pattern of the EHD1 and EHD2 genes expression and on their interaction with other cellular proteins it is concluded that the protein products of these genes participate in clathrin coated pit mediated endocytosis of IGF1 receptor, following its binding to its ligand.
According to one aspect of the present invention there is provided an isolated nucleic acid comprising a genomic, complementary or composite polynucleotide sequence encoding a polypeptide having an N-terminal region containing a nucleotide binding consensus site, a central coiled-coil structure and a C-terminal region including an eps15 homology (EH) domain. According to a preferred embodiment the polypeptide encoded by the polynucleotide participates in endocytosis processes.
The polynucleotide according to this aspect of the present invention preferably encodes a polypeptide which is at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
According to preferred embodiments, the polynucleotide according to this aspect of the present invention encodes a polypeptide as set forth in SEQ ID NOs:4, 5, 9 or 10 or a portion thereof, preferably a portion which retains EHD1 or 2 activity.
Alternatively or additionally, the polynucleotide according to this aspect of the present invention is preferably hybridizable with SEQ ID NOs:1, 2, 3, 6, 7 or 8.
Hybridization for long nucleic acids (e.g., above 200 bp in length) is effected according to preferred embodiments of the present invention by stringent or moderate hybridization, wherein stringent hybridization is effected by a hybridization solution containing 10% dextrane sulfate, 1 M NaCl, 1% SDS and 5xc3x97106 cpm 32p labeled probe, at 65xc2x0 C., with a final wash solution of 0.2xc3x97SSC and 0.1% SDS and final wash at 65xc2x0 C.; whereas moderate hybridization is effected by a hybridization solution containing 10% dextrane sulfate, 1 M NaCl, 1% SDS and 5xc3x97106 cpm 32p labeled probe, at 65xc2x0 C., with a final wash solution of 1xc3x97SSC and 0.1% SDS and final wash at 50xc2x0 C.
Yet alternatively or additionally, the polynucleotide according to this aspect of the present invention is preferably at least 70% identical with SEQ ID NOs: 1, 2, 3, 6, 7 or 8 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap weight equals 50, length weight equals 3, average match equals 10 and average mismatch equals xe2x88x929. According to preferred embodiments the polynucleotide according to this aspect of the present invention is as set forth in SEQ ID NOs:1, 2, 3, 6, 7 or 8 or a portion thereof, said portion preferably encodes a polypeptide retaining EHD1 or 2 activity.
According to another aspect of the present invention there is provided a nucleic acid construct comprising the isolated nucleic acid described herein. According to a preferred embodiment the nucleic acid construct according to this aspect of the present invention further comprising a promoter for regulating expression of the isolated nucleic acid in a sense or antisense orientation.
Alternatively, the nucleic acid construct according to this aspect of the present invention further comprising a positive and a negative selection markers and may therefore be employed for selecting homologous recombination events, including, but not limited to, homologous recombination employed in knock-in and knock-out procedures.
Consequently, according to yet another aspect of the present invention there is provided a host cell or animal comprising a nucleic acid construct as described herein.
According to still another aspect of the present invention there is provided an oligonucleotide of at least 17 bases specifically hybridizable with the isolated nucleic acid described herein. Hybridization of shorter nucleic acids (below 200 bp in length, e.g. 17-40 bp in length) is effected by stringent, moderate or mild hybridization, wherein stringent hybridization is effected by a hybridization solution of 6xc3x97SSC and 1% SDS or 3 M TMACI, 0.01 M sodium phosphate (pH 6.8), 1 mM EDTA (pH 7.6), 0.5% SDS, 100 xcexcg/ml denatured salmon sperm DNA and 0.1% nonfat dried milk, hybridization temperature of 1-1.5xc2x0 C. below the Tm, final wash solution of 3 M TMACI, 0.01 M sodium phosphate (pH 6.8), 1 mM EDTA (pH 7.6), 0.5% SDS at 1-1.5xc2x0 C. below the Tm; moderate hybridization is effected by a hybridization solution of 6xc3x97SSC and 0.1% SDS or 3 M TMACI, 0.01 M sodium phosphate (pH 6.8), 1 mM EDTA (pH 7.6), 0.5% SDS, 100 xcexcg/ml denatured salmon sperm DNA and 0.1% nonfat dried milk, hybridization temperature of 2-2.5xc2x0 C. below the Tm, final wash solution of 3 M TMACI, 0.01 M sodium phosphate (pH 6.8), 1 mM EDTA (pH 7.6), 0.5% SDS at 1-1.5xc2x0 C. below the Tm, final wash solution of 6xc3x97SSC, and final wash at 22xc2x0 C.; whereas mild hybridization is effected by a hybridization solution of a hybridization solution of 6xc3x97SSC and 1% SDS or 3 M TMACI, 0.01 M sodium phosphate (pH 6.8), 1 mM EDTA (pH 7.6), 0.5% SDS, 100 xcexcg/ml denatured salmon sperm DNA and 0.1% nonfat dried milk, hybridization temperature of 37xc2x0 C., final wash solution of 6xc3x97SSC and final wash at 22xc2x0 C.
According to an additional aspect of the present invention there is provided a pair of oligonucleotides each of at least 17 bases specifically hybridizable with the isolated nucleic acid described herein in an opposite orientation so as to direct exponential amplification of a portion thereof in a nucleic acid amplification reaction.
According to yet an additional aspect of the present invention there is provided a nucleic acid amplification product obtained using the pair of primers described herein.
According to still an additional aspect of the present invention there is provided an antisense oligonucleotide comprising a polynucleotide or a polynucleotide analog of at least 10 bases being hybridizable in vivo, under physiological conditions, with a portion of a polynucleotide strand encoding a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
According to a further aspect of the present invention there is provided a pharmaceutical composition comprising the antisense oligonucleotide described herein and a pharmaceutically acceptable carrier.
According to still a further aspect of the present invention there is provided a ribozyme comprising the antisense oligonucleotide described herein and a ribozyme sequence fused thereto.
According to yet a further aspect of the present invention there is provided a recombinant protein comprising a polypeptide having an N-terminal region containing a nucleotide binding consensus site, a central coiled-coil structure and a C-terminal region including an eps15 homology (EH) domain, the polypeptide participates in endocytosis. Preferably, the polypeptide is at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2. Most preferably the polypeptide includes at least a portion of SEQ ID NOs:4, 5, 9 or 10. Additionally or alternatively, the polypeptide according to this aspect of the present invention is preferably encoded by a polynucleotide hybridizable with SEQ ID NOs: 1, 2, 3, 6, 7 or 8 or a portion thereof under the any of the stringent or moderate hybridization conditions described above for long nucleic acids. Still additionally or alternatively, the polypeptide according to this aspect of the present invention is preferably encoded by a polynucleotide at least 70% identical with SEQ ID NOs: 1, 2, 3, 6, 7 or 8 or portions thereof as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap weight equals 50, length weight equals 3, average match equals 10 and average mismatch equals xe2x88x929.
According to still a further aspect of the present invention there is provided a pharmaceutical composition comprising, as an active ingredient, the recombinant protein described herein and a pharmaceutical acceptable carrier.
According to another aspect of the present invention there is provided a peptide or a peptide analog comprising a stretch of at least 6 consecutive amino acids or analogs thereof derived from a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2. Preferably, the peptide or a peptide analog according to this aspect of the present invention comprises a stretch of at least 6 consecutive amino acids or analogs thereof derived from SEQ ID NOs:4, 5, 9 or 10.
According to still another aspect of the present invention there is provided a display library comprising a plurality of display vehicles (such as phages, viruses or bacteria) each displaying at least 6 consecutive amino acids derived from a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2. According to a preferred embodiment of this aspect of the present invention substantially every 6 consecutive amino acids derived from the polypeptide are displayed by at least one of the plurality of display vehicles, so as to provide a highly representative library. Preferably, the consecutive amino acids or amino acid analogs of the peptide or peptide analog according to this aspect of the present invention are derived from SEQ ID NOs:4, 5, 9 or 10.
According to still another aspect of the present invention there is provided an antibody comprising an immunoglobulin specifically recognizing a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2. According to a preferred embodiment of this aspect of the present invention the antibody specifically recognizing the polypeptides set forth in SEQ ID NOs:4, 5, 9 or 10. The antibody according to this aspect of the present invention can be, for example, a polyclonal antibody, a monoclonal antibody, a humanized antibody, a single chain antibody or an immunoreactive derivative (e.g., portion) of an antibody.
According to yet another aspect of the present invention there is provided a pharmaceutical composition comprising, as an active ingredient, an agent for regulating an endogenous protein activity in vivo, the endogenous protein being at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
According to yet another aspect of the present invention there is provided a method of regulating an endogenous protein activity in vivo the method comprising the steps of administering an agent for regulating the endogenous protein activity in vivo, the endogenous protein being at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
According to further features in preferred embodiments of the invention described below, the agent indirectly serves for regulating. IGF1 receptor cell signaling via altered clathrin coated pit mediated endocytosis.
According to still further features in the described preferred embodiments the agent serves for upregulating the activity.
According to still further features in the described preferred embodiments the agent indirectly serves for downregulating IGF1 receptor cell signaling via upregulated clathrin coated pit mediated endocytosis.
According to still further features in the described preferred embodiments the agent serves for upregulating clathrin coated pit mediated endocytosis.
According to still further features in the described preferred embodiments the agent includes an expressible sense polynucleotide at least 70% identical with SEQ ID NOs: 1, 2, 3, 6, 7 or 8 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap weight equals 50, length weight equals 3, average match equals 10 and average mismatch equals xe2x88x929.
According to still further features in the described preferred embodiments the agent includes a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
According to still further features in the described preferred embodiments the agent serves for downregulating the activity.
According to still further features in the described preferred embodiments the agent indirectly serves for upregulating IGF1 receptor cell signaling via downregulated clathrin coated pit mediated endocytosis.
According to still further features in the described preferred embodiments the agent includes an expressible antisense polynucleotide at least 70% identical with SEQ ID NOs: 1, 2, 3, 6, 7 or 8 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap weight equals 50, length weight equals 3, average match equals 10 and average mismatch equals xe2x88x929.
According to still further features in the described preferred embodiments the agent includes an antisense oligonucleotide which includes a polynucleotide or a polynucleotide analog of at least 10 bases which is hybridizable in vivo, under physiological conditions, with a portion of a polynucleotide strand encoding a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
According to still further features in the described preferred embodiments the agent includes a peptide or a peptide analog representing a stretch of at least 6 consecutive amino acids or analogs thereof derived from a polypeptide at least 75% homologous to SEQ ID NOs:4, 5, 9 or 10 as determined using the BestFit software of the Wisconsin sequence analysis package, utilizing the Smith and Waterman algorithm, where gap creation penalty equals 8 and gap extension penalty equals 2.
The present invention successfully addresses the shortcomings of the presently known configurations by providing new means to treat diseases or conditions associated with too high or alternatively too low IGF1 receptor signaling.